Eosinophilic esophagitis and hen's egg tolerance: two cases highlighting remission with strongly heated but not less heated hen's egg despite topical steroid treatment

Lisa Nuyttens ^1,2* Liselot De Vlieger ¹ Toon Ieven ^1,3 Marianne Diels ² Tessa Bosmans ⁴ Sara Van Meerbeeck ⁴ Tine Alliet ² Toon Dominicus ² Ilse Hoffman ⁴ Dominique MA Bullens ^1,2

• ¹ Allergy and Clinical Immunology Research Group, Department of Microbiology, Immunology & Transplantation, KU Leuven, Leuven, Belgium
• ² Department of Pediatrics, University Hospitals Leuven, Leuven, Brussels, Belgium
• ³ Department of General Internal Medicine, Division of Allergy and Clinical Immunology, University Hospitals Leuven, Leuven, Belgium
• ⁴ pediatric Gastroenterology, Hepatology and Nutrition, University Hospitals Leuven, Leuven, Belgium

Eosinophilic esophagitis (EoE) is a chronic, antigen-mediated disease characterized by eosinophilic inflammation of the esophagus. Common triggers in Europe include cow's milk, hen's egg, wheat, soy, (pea)nuts, and (shell)fish. Recent studies indicate that heated forms of cow's milk in cow's milkinduced EoE may be well tolerated. Similarly to cow's milk, we present two cases of children with hen's egg-triggered pediatric EoE, although treated with topical steroids, who remained in remission after the introduction of strongly heated forms of hen's egg. The introduction of lesser heated forms, however, led to relapse. These two cases suggest that heated hen's egg might be well tolerated in hen's egg-induced pediatric EoE, potentially allowing for a less restrictive diet and improved quality of life. Further research is necessary to explore the potential for inducing less heated and/or raw egg tolerance through gradual introduction of heated egg products.